I've taken a list of English words, and examined each of them to see what they sound like (using the PHP metaphone function). This page lists the most common metaphone codes, along with their words. You can also search for a word of your own, and see which words sound similar - and which ones rhyme, and which ones alliterate.
narcs narcos narcose narks
arcs narcs marcs marks recs arks narcos reracks orcs narks arracks wracks crocs carracks larks lyrics circus seracs darks tarocs torics tracks turacos charks maracas rocs arcus mercs triacs durocs torcs sarks darics quarks caracks cercus parks touracos orcas warks cracks racks hayracks carks harks fracas barracks barks barcas sharks
narc narco naric nark narky snark snarky